Datasheet

V
IN
C
IN
C
OUTCL
ON
CL
VIN
GND
TPS22946
OC
VOUT
ON
EN
VIN
TPS72018
GND
VOUT
LDO_EN
C
OUTLDO
TPS22946
SLVS984A –SEPTEMBER 2009–REVISED FEBRUARY 2010 www.ti.com
Automatic Disable in Case of Permanent Over Current
When the switch enters the current-limiting mode due to a hard short condition or a moderate over-current
condition, TPS22946 goes through the 10-ms blanking state and the 70-ms auto restart state. If the hard-short
condition or the moderate over-current condition persists after 5 s, the part shuts off regardless of the ON signal.
The switch is turned on again after a power reset if the ON pin is HIGH.
Inrush Current Timeout Feature
The inrush current required by the LDO at startup can in some cases exceed the current limit and initiate a
blanking (current limiting) condition. TPS22946 provides allowance for this scenario by temporarily increasing the
current limit to 435 mA for 8 ms after the load switch is enabled. This timeout is initiated by the positive edge
transition on the ON signal.
Figure 30. Inrush Current Timeout Circuit
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Product Folder Link(s): TPS22946